Liposomes and nanotechnology in drug development: focus on ocular targets

Abstract

Abstract:Poor drug delivery to lesions in patients' eyes is a major obstacle to the treatment of ocular diseases. The accessibility of these areas to drugs is highly restricted by the presence of barriers, including the corneal barrier, aqueous barrier, and the inner and outer blood-retinal barriers. In particular, the posterior segment is difficult to reach for drugs because of its structural peculiarities. This review discusses various barriers to drug delivery and provides comprehensive information for designing nanoparticle-mediated drug delivery systems for the treatment of ocular diseases. Nanoparticles can be designed to improve penetration, controlled release, and drug targeting. As highlighted in this review, the therapeutic efficacy of drugs in ocular diseases has been reported to be enhanced by the use of nanoparticles such as liposomes, micro/ nanospheres, microemulsions, and dendrimers. Our recent data show that intravitreal injection of targeted liposomes encapsulating an angiogenesis inhibitor caused significantly greater suppression of choroidal neovascularization than did the injection of free drug. Recent progress in ocular drug delivery systems research has provided new insights into drug development, and the use of nanoparticles for drug delivery is thus a promising approach for advanced therapy of ocular diseases.

Nanodrugs: pharmacokinetics and safety

“…28 Drug payloads can be either entrapped within the dendrimer scaffold via the generation of noncovalent complexes or linked to the dendrimer surface via covalent conjugation, so dendrimers can incorporate a lower amount of drugs than other carriers. 29 Covalently constructed dendritic macromolecules have the advantage of more specific control over drug release and may be designed to limit drug release in the systemic circulation and to trigger release under tumorspecific conditions (Table 2). 30 Dendritic polymers have recently been shown to improve the delivery of doxorubicin and other cytotoxic drugs to solid tumors and to reduce their accumulation in noncancerous tissues.…”

Preparation and ocular pharmacokinetics of hyaluronan acid-modified mucoadhesive liposomes

“…Methods such as hydrogels, polymeric micelles, and nanocarriers were widely used in this area (Li et al, 2008;Shen et al, 2009;Gupta et al, 2010;Li et al, 2012;Liu et al, 2012;Gan et al, 2013). Liposomes, a kind of closed vesicles composed of a phospholipid bilayer and an aqueous phase (Honda et al, 2013), have been serving as a promising ocular drug delivery method for the past decade (Li et al, 2009). Studies have demonstrated that by applying this method, a controlled drug release as well as membrane permeability can be achieved.…”

Nanoparticulate Transscleral Ocular Drug Delivery

“…Multifunctional nanoemulsions for oral and intravenous delivery: Gadolinium-loaded nanoemulsion has been utilized for brain imaging in animal studies [114][115][116][117][118][119][120][121][122][123][124][125][126][127][128][129][130][131][132][133]134]. This imaging technology could be utilized for imaging within the eye to observe the results of various drug delivery modalities.…”